THE HUMAN DECORIN GENE - INTRON EXON ORGANIZATION, DISCOVERY OF 2 ALTERNATIVELY SPLICED EXONS IN THE 5' UNTRANSLATED REGION, AND MAPPING OF THE GENE TO CHROMOSOME-12Q23
THE HUMAN DECORIN GENE - INTRON EXON ORGANIZATION, DISCOVERY OF 2 ALTERNATIVELY SPLICED EXONS IN THE 5' UNTRANSLATED REGION, AND MAPPING OF THE GENE TO CHROMOSOME-12Q23
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DOI：
10.1006/geno.1993.1022
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发表时间：
1993-01-01
期刊：
影响因子：
4.4
通讯作者：
IOZZO, RV
中科院分区：
文献类型：
--
作者：
DANIELSON, KG;FAZZIO, A;IOZZO, RV
Decorin是一种由大多数血管和无血管结缔组织表达的软骨素/硫酸皮肤素蛋白多糖，由于其与胶原蛋白和生长因子相互作用的能力，已被认为与基质组装和细胞生长的控制有关。为了了解参与调节其组织表达的分子机制，我们分离了一些编码完整decorin基因的基因组克隆。人类decorin基因全长超过38kb，包含8个外显子和非常大的内含子，其中两个是5.4和> 13.2 kb。我们在5 '非翻译区发现了两个交替剪接的先导外显子Ia和Ib。这些外显子是通过对成纤维细胞cDNA文库进行聚合酶链反应扩增获得的cDNA进行克隆和测序鉴定的。利用Northern blotting或逆转录酶PCR，我们检测了从人类细胞系和组织中分离的多种mrna中的两个先导外显子。有趣的是，在禽类和牛decorin的5 '非翻译区分别发现了与Ia和Ib高度同源的序列（74-87%）。这种物种间的高度保守表明这些先导外显子具有调控功能。在3 '非翻译区有几个聚腺苷化位点，其中至少两个位点可以产生≈1.6和≈1.9 kb的转录本，通常在各种组织和细胞中检测到。利用基因组克隆作为标记探针，对人类中期染色体进行原位杂交，将decorin基因定位到人类染色体12q23的离散区域。这项研究为识别decorin基因的转录控制提供了分子基础，并为研究与这一重要人类基因相关的遗传疾病提供了机会。
Decorin is a chondroitin/dermatan sulfate proteoglycan expressed by most vascular and avascular connective tissues and, because of its ability to interact with collagen and growth factors, has been implicated in the control of matrix assembly and cellular growth. To understand the molecular mechanisms involved in regulating its tissue expression, we have isolated a number of genomic clones encoding the complete decorin gene. The human decorin gene spans over 38 kb of continuous DNA sequence and contains eight exons and very large introns, two of which are 5.4 and > 13.2 kb. We have discovered two alternatively spliced leader exons, exons Ia and Ib, in the 5′ untranslated region. These exons were identified by cloning and sequencing cDNAs obtained by polymerase chain reaction amplification of a fibroblast cDNA library. Using Northern blotting or reverse transcriptase PCR, we detected the two leader exons in a variety of mRNAs isolated from human cell lines and tissues. Interestingly, sequences highly (74-87%) homologous to exons Ia and Ib are found in the 5′ untranslated region of avian and bovine decorin, respectively. This high degree of conservation among species suggests regulatory functions for these leader exons. In the 3′ untranslated region there are several polyadenylation sites, and at least two of these sites could give rise to the transcripts of ≈ 1.6 and ≈ 1.9 kb, typically detected in a variety of tissues and cells. Using a genomic clone as the labeled probe andin situhybridization of human metaphase chromosomes, we have mapped the decorin gene to the discrete region of human chromosome 12q23. This study provides the molecular basis for discerning the transcriptional control of the decorin gene and offers the opportunity to investigate genetic disorders linked to this important human gene.